1. Field of the Invention
The present invention relates to a liquid developer.
2. Description of the Related Art
In a liquid developer used for an electrophotographic image forming apparatus, carbon black is widely used as a pigment (coloring material) for obtaining a black image.
For example, Japanese Laid-Open Patent Publication No. 52-037435 (hereinafter “Patent Document 1”) discloses that carbon black and copper phthalocyanine are mixed for adjusting the tone of black.
In addition, Japanese Laid-Open Patent Publication No. 09-269615 (hereinafter “Patent Document 2”) discloses that two or more types of coloring agents are used in combination in order to improve various physical properties.
Moreover, Japanese Laid-Open Patent Publication No. 2009-133973 (hereinafter “Patent Document 3”) discloses that a nigrosine-based dye is used as a charge control agent, in combination with carbon black.